Tiny USDZ library in C++14

TinyUSDZ is dependency-free(depends only on C++ STL. Other 3rd-party libraries included. Yes, you don't need pxrUSD library!) USDZ/USDC/USDA library written in C++14.

Status

TinyUSDZ is near to release first working version. Remaining task is to write a examples, demo and scene/render delegate(Tydra)

• USDZ/USDC(Crate) parser
• USDZ/USDC(Crate) writer (Work-in-progress)
• USDA parser
• USDA writer
• Support basic Primitives(Xform, Mesh, BasisCurves, etc.), basic Lights and Shaders(UsdPreviewSurface, UsdUVTexture, UsdPrimvarReader)

Please see doc/status.md for more details

• Write simple SDL viewer example(2022 Fall expected)
• Write iOS and Android example(2022 Fall expected)
• Vulkan raytracing viewer example
• USD <-> glTF converter example
• Web demo with Three.js?
  • Three.js started to support USDZ with Ascii format, but no USDC support yet: https://github.com/mrdoob/three.js/issues/14219

Web platform and sandboxed environment

TinyUSDZ does not use C++ exceptions and can be built without threads. TinyUSDZ supports WASM and WASI build. So TinyUSDZ should runs well on various Web platform(WebAssembly. No SharedArrayBuffer, Atomics and WebAssembly SIMD(which is not yet available on iOS Safari) required) and sandboxed environment(WASI. Users who need to read various USD file which possibly could contain malcious data from Internet, IPFS or blockchain storage).

Tydra

USD itself is a generic container of 3D scene data. Tydra is an interface to Renderers/Viewers and other DCCs. Tydra may be something like Tiny version of pxrUSD Hydra, but its API is completely different. See src/tydra/README.md for the background.

• Image color space
  • sRGB
  • Linear
  • Rec.709
  • Partial support of OCIO(OpenColor IO) through TinyColorIO https://github.com/syoyo/tinycolorio . Currently SPI3DLut only.

Notice

TinyUSDZ does not support Reality Composer file format(.reality) since it uses proprietary file format and we cannot understand it(so no conversion support from/to Reality also).

Commercial support

TinyUSDZ focuses on loading/writing USDA/USDC/USDZ functionalities. Example viewer is just for demo purpose. Currently TinyUSDZ project is run as personal project by syoyo and syoyo does not provide commercial support as an individual.

If you need commercial support, eco-system development(e.g. plug-ins, DCC tools on top of TinyUSDZ) or production-grade USDZ model viewer(e.g. embed TinyUSDZ to your AR app, 3D NFT Android mobile viewer capable of displaying (encrypted) USDZ model), please contact Light Transport Entertainment, Inc. : https://goo.gl/forms/1p6uGcOKWGpXPHkA2

Other related projects

• UsdzSharpie: C# Simple implementation of Usdz file format ( https://github.com/UkooLabs/UsdzSharpie )
• TinyGLTF: glTF 2.0 loader/saver ( https://github.com/syoyo/tinygltf )
• USD-build-aarch64: Full USD build for AARCH64(Linux and Android): https://github.com/syoyo/USD-build-aarch64
• BlenderUSDZ: It contains their own Python USDC parser/serializer. https://github.com/robmcrosby/BlenderUSDZ

Supported platforms

• Linux 64bit or later
  • ARM AARCH64
  • x86-64
  • RISC-V(Should work)
  • SPARC, POWER(Big endian machine). May work(theoretically)
• Android arm64v8a
• iOS
• macOS(Arm, x86-64)
• Windows 10 64bit or later
  • Windows ARM(should work)
• WebAssembly
  • Emscripten
    • See examples/sdlviewer/ example.
• WASI(through WASI toolchain)
  • See sandbox/wasi

Requirements

• C++14 compiler
  • gcc 4.9 or later
  • Visual Studio 2019 or later(2017 may compiles)
    • Can be compiled with standalone MSVC compilers(Build Tools for Visual Studio 2019)
  • clang 3.4 or later https://clang.llvm.org/cxx_status.html
  • llvm-mingw(clang) supported

USDZ file format

USDZ is actually an uncompressed zip file. USDZ(ZIP) contains usd(binary or ascii) and resources(e.g. image/auduo files)

Security and memory budget

USDZ(USDC) is a binary format and data are compressed. To avoid out-of-bounds access, out-of-memory, and other security issues when loading malcious USDZ(e.g. USDZ file from unknown origin), TinyUSDZ has a memory budget feature to avoid out-of-memory issue.

To limit a memory usage when loading USDZ file, Please set a value max_memory_limit_in_mb in USDLoadOptions.

TinyUSDZ source codes are also checked by Address Sanitizer, CodeQL and Fuzzer.

If you need to deal with arbitrary USD files from unknown origin(e.g. from internet, NFT storage. Whose may contain malcious data), it is recommended to use TinyUSDZ in sandboxed environment(RunC, FlatPak, WASI(WASM)). Run in WASI is recommended at the moment. See sandbox/wasi/ for Building TinyUSDZ with WASI toolchain.

Build

Integrate to your app

Recomended way is simply copy src and include folder to your app, and add *.cc files to your app's build system. See <tinyusdz>/CMakeLists.txt and examples/sdlviewer/CMakeLists.txt for details.

It may not be recommend to use tinyusdz as a git submodule, since the repo contains lots of codes required to build TinyUSDZ examples but these are not required for your app.

Compiler defines

Please see CMake build options and CMakeLists.txt. In most case same identifier is defined from cmake build options: For example if you specify -DTINYUSDZ_PRODUCTION_BUILD=1 for cmake argument, TINYUSDZ_PRODUCTION_BUILD is defined.

CMake

cmake build is still provided for CI build. CMakeSettings.json is provided for Visual Studio 2019.

Cmake project is not recommended for embedding TinyUSDZ to your app.

$ mkdir build
$ cd build
$ cmake ..
$ make

LLVM-MinGW build

MinGW native and cross-compiling example using llvm-mingw(clang) is provided. See scripts/bootstrap-cmake-mingw-win.sh and scripts/bootstrap-cmake-llvm-mingw-cross.sh for details.

One of benefit to use llvm-mingw is address sanitizer support on Windows app.

To run app(.exe, you'll need libunwind.dll and libc++.dll on your working directory or search path)

For Windows native build, we assume ninja.exe is installed on your system(You can use it from Meson package)

CMake build options

• TINYUSDZ_PRODUCTION_BUILD : Production build. Do not output debugging logs.
• TINYUSDZ_BUILD_TESTS : Build tests
• TINYUSDZ_BUILD_EXAMPLES : Build examples(note that not all examples in examples folder are built)
• TINYUSDZ_WITH_OPENSUBDIV : Use OpenSubviv to tessellate subdivision surface.
  • OpenSubdiv code is included in TinyUSDZ repo. If you want to use external OpenSubdiv repo, specity the path to OpenSubdiv using osd_DIR cmake environment variable.
• TINYUSDZ_WITH_AUDIO : Support loading audio(mp3 and wav).
• TINYUSDZ_WITH_EXR : Support loading EXR format HDR texture through TinyEXR.
• TINYUSDZ_WITH_PXR_COMPAT_API : Build with pxrUSD compatible API.

clang-cl on Windows

Assume ninja.exe is installed and path to ninja.exe is added to your %PATH%

Edit path to MSVC SDK and Windows SDK in bootstrap-clang-cl-win64.bat, then

> bootstrap-clang-cl-win64.bat
> ninja.exe

Fuzzer

See tests/fuzzer . For building fuzzer tests, you'll need Meson and Ninja.

Examples

• usda_parser Parse USDA and print it as Ascii.
• Simple usdz_dump Parse USDC and print it as Ascii.
• Simple SDL viewer
  • Separated CMake build provided: See Readme

See examples directory for more examples, but may not actively maintained except for the above examples.

USDZ Data format

See prim_format.md and preview_surface.md

Blender add-on(will be removed)

There was some experiements of TinyUSDZ add-on for Blender.

But Blender's USD support is getting better. We recommend to use Omniverse version of Blender's USD import/export feature.

https://builder.blender.org/download/experimental/

Build Blender add-on on Linux(deprecared)

Edit path to python interpreter in scripts/bootstrap-cmake-linux-blender-pymodule.sh, then

$ ./scripts/bootstrap-cmake-linux-blender-pymodule.sh
$ cd build
$ make

Copy tinyusd_blender.*-linux-gnu.so to blender's folder. Recommended location is USER folder(~/.config/blender/2.xx)

Create scripts/addons/modules folder if required

mkdir -p ~/.config/blender/2.93/scripts/addons/modules

TODO

Higher priority

• Built-in usdObj(wavefront .obj mesh) support.
  • Through tinyobjloader.
• Support Crate(binary) version 0.8.0(USD v20.11 default)
• Animation
  • Skinning(usdSkel)
  • Blend shapes
    • In-between blend shapes
• Read USD data with bounded memory size. This feature is especially useful for mobile platform(e.g. in terms of security, memory consumption, etc)
• USDC writer
• Support Nested USDZ
• UDIM texture support
• MaterialX support
  • Parse XML file

Lower priority

• iOS example?
• Support AR related schema(Game-like feature added by Reality Composer?)
• Audio play support
  • Play audio using SoLoud or miniaudio(or Oboe for Android)
  • wav(dr_wav)
  • mp3(dr_mp3)
  • m4a?
• Viewer with Vulkan API.
• Replace OpenSubdiv with our own subdiv library.
• Write parser based on the schema definition.
• Support big endian architecture.

Python binding and prebuit packages

Python binding and prebuilt packages(uploadded on PyPI) are provided.

See python/README.md and doc/python_binding.md for details.

CI build

CI build script is a build script trying to build TinyUSDZ in self-contained manner as much as possible(including custom Python build)

Linux/macOS

T.B.W.

Windows

Build custom Python,

> ci-build-python-lib.bat

then build TinyUSDZ by linking with this local Python build.

> ci-build-vs2022.bat

License

TinyUSDZ is licensed under MIT license.

Third party licenses

• pxrUSD : Apache 2.0 license. https://github.com/PixarAnimationStudios/USD
• OpenSubdiv : Apache 2.0 license. https://github.com/PixarAnimationStudios/OpenSubdiv
• lz4 : BSD-2 license. http://www.lz4.org
• cnpy(uncompressed ZIP decode/encode code) : MIT license https://github.com/rogersce/cnpy
• tinyexr: BSD license.
• tinyobjloader: MIT license.
• tinygltf: MIT license.
• tinycolorio: MIT license. https://github.com/syoyo/tinycolorio
• stb_image: public domain.
• dr_libs: public domain. https://github.com/mackron/dr_libs
• miniaudio: public domain or MIT no attribution. https://github.com/dr-soft/miniaudio
• SDL2 : zlib license. https://www.libsdl.org/index.php
• optional-lite: BSL 1.0 license. https://github.com/martinmoene/optional-lite
• expected-lite: BSL 1.0 license. https://github.com/martinmoene/expected-lite
• mapbox/earcut.hpp: ISC license. https://github.com/mapbox/earcut.hpp
• par_shapes.h generate parametric surfaces and other simple shapes: MIT license https://github.com/prideout/par
• staticstruct: MIT license. https://github.com/syoyo/staticstruct
• MaterialX: Apache 2.0 license. https://github.com/AcademySoftwareFoundation/MaterialX
• tinyxml2: zlib license. https://github.com/leethomason/tinyxml2
• string_id: zlib license. https://github.com/foonathan/string_id
• cityhash: MIT license. https://github.com/google/cityhash
• fast_float: Apache 2.0/MIT dual license. https://github.com/fastfloat/fast_float
• jsteeman/atoi: Apache 2.0 license. https://github.com/jsteemann/atoi
• formatxx: unlicense. https://github.com/seanmiddleditch/formatxx
• mapbox/variant: BSD-3 or BSL-1.0 license. https://github.com/mapbox/variant
• ubench.h: Unlicense. https://github.com/sheredom/ubench.h
• thelink2012/any : BSL-1.0 license. https://github.com/thelink2012/any
• simple_match : BSL-1.0 license. https://github.com/jbandela/simple_match
• nanobind : BSD-3 license. https://github.com/wjakob/nanobind
• pybind11 : BSD-3 license. https://github.com/pybind/pybind11
• pystring : BSD-3 license. https://github.com/imageworks/pystring
• gulrak/filesytem : MIT license. https://github.com/gulrak/filesystem
• p-ranav/glob : MIT license. https://github.com/p-ranav/glob
• linalg.h : Unlicense. https://github.com/sgorsten/linalg
• mapbox/eternal: ISC License. https://github.com/mapbox/eternal
• bvh: MIT license. https://github.com/madmann91/bvh
• dtoa_milo.h: MIT License. https://github.com/miloyip/dtoa-benchmark
• jeaiii/itoa: MIT License. https://github.com/jeaiii/itoa